Feathers are continuing to fly over Black Swan. Darren Aronofsky's movie, for which Natalie Portman won an Oscar, is about a ballerina losing her grip on reality as she prepares to dance Swan Lake. Portman took ballet classes in preparation for the role, but Sarah Lane of American Ballet Theatre has claimed that she did the actual classical dancing, which includes pointe work. Her face was then, it seems, digitally replaced by Portman's. Lane, who worked on the film for more than six weeks, was also used for the full body-shots and just-the-legs shots.

Lane was not credited for her work as Portman's dance-double, however, nor was she on the longish list of people thanked by Portman in her Oscar acceptance speech. In addition, she was suddenly and spookily deleted from a video circulating online which showed the face-replacement special effects used in Black Swan. In the online Dance Magazine, journalist Wendy Perron wrote of a "blackout" and a "propaganda of omissions" relating to the ABT soloist. None of this surprised Lane, because by then a Fox Searchlight producer had called to ask her to stop giving interviews until after the Oscars. "They were trying to create this facade that she (Portman) had become a ballerina in a year and a half," she said. "So I knew they didn't want to publicize anything about me."

Portman's fiancé, the choreographer and New York City Ballet dancer Benjamin Millepied, who worked on the film, denies Lane's claim that Portman did no more than 5% of the dancing. "Honestly, 85% of that movie is Natalie" Millepied told the Los Angeles Times earlier this week, and his version is backed up by Aronofsky. If it sounds like a storm in a teacup, there's big money at stake. The story of Portman's supposed transformation from actress into ballerina is a large part of the film's appeal, and was almost certainly a factor in her winning the Oscar. If that story is called into question, then so is Portman's credibility.

There's another dimension to the spat, concerning Millepied. Before Black Swan the 33-year-old dancer-choreographer was involved with a colleague of Lane's at ABT, dancer Isabella Boylston. The two had been living together in New York's East Village, and very much an item. While working on the film, however, he became involved with Portman, and not long afterwards it was announced that an "indescribably happy" Portman was pregnant and that the couple were engaged.

Underlying all of this is a clash of cultures: that of Hollywood, with its colossal paychecks, and the pinched, underfunded world of ballet. It takes upward of ten thousand classroom hours to make a professional ballet dancer, and while most dancers are happy to receive scant financial reward (the $2000 a week after taxes that Lane made on Black Swan may well have been the most she's ever earned), they do appreciate respect.

It seems obvious to me as a critic how much of the movement ascribed to Portman's character is actually performed by a professional. Portman may have taken classes for a few months, but her body-shape, musculature and deportment are nothing like a classical dancer's. What those classes did achieve was to give her a certain amount of dancerly attitude. The way she wears her clothes and slouches around in her practice-kit is well-observed, and the minutiae of darning and breaking in pointe shoes is spot-on. Portman acted well in Black Swan, but if she has failed to acknowledge Lane's contribution, she may have acted pretty gracelessly too.